Charging aux and main batteries, please help, urgent

[jvannghi]

Hey guys,

Got a 2001 fleetwood expedition diesel that i rarely use and constantly have electrical gremlins, possibly from my own ignorance.

Replaced all batteries in jan, put on 120v power for the last 8 months with main and aux switched off. Come back to start and batteries all dead.

Thought something wrong with ac so left generator on for about 10hrs and it didnt charge. Had aux and main switch off, not sure if that matters, assumed it would charge quicker with it all off.

Think i killed my batteries again? How do i charge the dang thing? Need to move it today.

Greatly appreciate any advice, couldnt find by doing a search here.

[Jyrocharlie]

Try turning the battery disconnects on. How did you start the generator?

[Ndrorder]

Many RVs will not charge the batteries when the switches are off. The next steps would depend on the actual voltage in the starting batteries before turning them on. If just moving, focus on the starting batteries.

[twinboat]

The switchs should be off only with NO shore or generator power.

If shore power is connected, leave the switchs on.

[jvannghi]

Thx so much for the replies, my logic was togally backwards, will start with turning switches back on!

Honestly dont know how/why gen started to begin with but battery level was all low and engine didnt even turn over.

Btw, think my batteries are roasted? Theyre deep cycle, new in jan but have no clue how long its been dead.

Thx again!

[Jyrocharlie]

Try charging them, they may be ok but a little weaker, you have a warranty on them, sometimes with FREE replacement in the first year.

[jvannghi]

Originally Posted by Jyrocharlie

Try charging them, they may be ok but a little weaker, you have a warranty on them, sometimes with FREE replacement in the first year.

Ok thx so much

[jvannghi]

On the same note, whats fastest to charge, 120 or generator?

Thx again

[wolfe10]

Originally Posted by jvannghi

On the same note, whats fastest to charge, 120 or generator?

Thx again

EXACTLY the same. Both merely provide 120 VAC to your charging device.

[Jyrocharlie]

it depends on your stand alone charger's amps, both will be fed by 120v but some chargers built in's charge at 20 amps and some stand alones are adjustable to 50 amps or more.

[Ray,IN]

Originally Posted by Jyrocharlie

it depends on your stand alone charger's amps, both will be fed by 120v but some chargers built in's charge at 20 amps and some stand alones are adjustable to 50 amps or more.

Yup, my inverter/charger may be set anywhere from 200A per hr for bulk charge down to 60A per hr for bulk charge. The setting depends on the size/capacity of the battery banks.

[Persistent]

Glad to see your issue has been solved!

There is a lot to learn about RV electrical systems. I don't have an Expedition, but here are a few pointers about such systems.

There are at least two 12 volt battery systems in an RV and one in a TT. The two are, "Chassis" for the engine and "House" for living area 12 volt power.

Generators sometimes start from chassis and sometimes start from house. It helps if you know which is true for your RV.

Manufacturers often install a "Disconnect" switch in a convenient place to turn most 12 volt house stuff off for storage. As you have discovered it often also turns charging off. However, the manufacturer switch probably leaves some safety and maybe automatic power monitoring systems on. With the batteries fully charged, you may get one to two weeks of storage before recharge is needed. Monitor battery voltage to know when to recharge. Keep them above 12.4 volts for best battery life.

Some owners install a second disconnect switch near the batteries. That one usually completely disconnects the 12 volt house batteries. Starting fully charged and with flooded cell batteries in excellent condition, you can usually store for 6 months before recharging. AGM batteries usually last for 12 months.

Measure the voltage at the battery terminals to know when to recharge. Keep the voltage during storage above 12.4 volts for long useful life. You apparently know it takes a long time to fully charge. Usually it takes 14 to 18 hours to fully clean the sulfate off the battery plates before storage.

As far as damage from drawing the batteries down flat is concerned, deep draw house batteries are resistant to damage. It does cost some life each time flooded cell batteries are excessively discharged. AGM batteries are much more resistant to flat out discharge. You probably won’t notice any difference.

Automotive start batteries are different. Deep or flat out discharge will probably decrease starting capacity and reduce cycle life. It will be most noticeable in cold weather. I don’t mean Florida cold weather. I mean Wisconsin cold weather.

There is a lot more to learn about your RV power systems and battery systems. Ask about what you are interested in.

I wish you good luck and happy trails ahead!